JP5791856B2 - Patient bed with magnetic resonance radio frequency antenna, especially for therapy system under magnetic resonance imaging guidance - Google Patents

Description

  The present invention provides a patient bed for supporting a subject's abdominal region, an MR radio frequency (RF) antenna device for the patient bed, and an MR radio frequency (RF), particularly during radiation therapy under magnetic resonance (MR) guidance. A) Radiation therapy system guided by an MR imaging device having a patient bed with an antenna device.

  In the prior art of treatment systems guided by magnetic resonance imaging devices, integrated magnetic resonance therapy (MR-T) systems are known that allow real-time MR monitoring of the patient under treatment. The treatment system may use at least one of ionizing radiation and ultrasonic energy for therapeutic purposes.

  Abdominal organs such as the prostate, cervix, kidney, and bladder show significant movement or deformation between and during radiotherapy sessions, so the most likely area of application for MR-T systems One is the therapeutic treatment of these abdominal organs.

  Since organ and lesion tracking is the primary purpose of integrated MR imaging, clear imaging of organs or lesion boundaries is essential. On the other hand, maximum diagnostic quality is not required because each image is taken in a preliminary stage prior to treatment planning.

  For diagnostic purposes requiring the highest imaging quality, these organs are imaged using a special local MRRF antenna (coil), for example a transrectal antenna. Since a local MRRF antenna can be placed in close proximity to a target area, eg, the prostate, a significantly better signal-to-noise ratio can be achieved, which can be about 10 times larger than using a trunk coil. However, these local MRRF antennas (coils) are often split due to concurrent chemotherapy, requiring bowel syndrome and frequent installation and disinfection for several weeks of treatment over several weeks. In therapeutic treatment, it is impractical from the viewpoint of workflow and patient comfort.

  MRRF antennas designed as surface coils are known to allow higher signal-to-noise ratios with local imaging without any need for intracavity applications, but reproducibly placed in exactly the same place This can lead to difficult absorption correction problems and hinder efficient workflow.

  For MR-T devices, MR imaging using an MRI system trunk coil is possible, but due to the lower signal-to-noise ratio, it is not sufficient for depiction of organs or lesions (eg in the case of the prostate ).

  High patient throughput for therapeutic treatment requires an efficient workflow (10-15 minute treatment session interval time). Since treatment radiation dose segmentation divides the treatment into 20 or more radiation sessions, maximum patient comfort is desired.

  Magnetic Resonance (MR) with improved patient throughput of therapeutic treatment, and improved patient comfort, considering 10-15 minute radiotherapy treatment session interval time and splitting into 20 or more radiation sessions It would be desirable to provide a means for guided radiation therapy.

  Accordingly, it is an object of the present invention to provide an abdomen of a subject, usually a patient, during magnetic resonance (MR) guided treatment using at least one of ionizing radiation and ultrasonic energy for therapeutic purposes. It is to provide a patient bed having a support for supporting the region and having the lying direction in which the subject is intended to lie along the lying direction.

  The patient bed has at least one magnetic resonance (MR) radio frequency (RF) antenna encapsulated in a housing having two opposite sides and is disposed in the patient bed central region on the upper surface of the patient bed, One magnetic resonance (MR) radio frequency (RF) antenna device. The MRRF antenna may be a coil type design or any other design deemed appropriate to those skilled in the art. The housing may be made of any non-magnetic material that provides sufficient mechanical strength while meeting the sterilization requirements applied in hospitals or medical centers.

  The MRRF antenna device further has a radiation detection device enclosed in a housing. The radiation detection device makes it possible to measure incident treatment radiation at a known location, which provides real-time data about the radiation at the known location for quality assurance, verification and documentation purposes. . Preferably, the radiation detection device is arranged at a position within the portion of the housing that includes the first third of the housing relative to the lying direction of the patient bed. As a result, the radiation detection apparatus is arranged close to the radiation exposure area inside the subject but outside, and the purpose of quality assurance can be achieved by measuring stray radiation dose at a known location. Furthermore, it may be possible to compare the measured radiation dose with the planning data in real time. If deviations from the planning data are detected, the radiation treatment can be corrected or interrupted quickly.

  In addition, the patient bed has two leg supports for supporting the subject's leg from below, and in at least one operational state, each side of the MRRF antenna device is proximal to the inner side of each of the subject's legs. In the at least one operational state, the MRRF antenna device is provided to be proximal to the perineum of the subject. This provides an MR signal with a high signal-to-noise ratio, while the patient bed is easy for the operator to use and the MRRF antenna application is comfortable for the subject. Further, the location where the inner side of each of the subject's legs is proximal to the side of the MRRF antenna device and the subject's perineum is proximal to the MRRF antenna device improves the positioning of the MRRF antenna relative to the subject. Repeatability and reproducibility can be provided essentially.

  The patient bed is provided with a securing member disposed along each of the sides of the patient bed and parallel to the patient bed recumbent direction, each of the securing members being in one of the legs of the subject in the at least one operating state. A higher degree of repeatability and reproducibility of the subject's position is obtained when provided to be at least on the outer proximal side.

  In a preferred embodiment, the patient bed is disposed on each side of the patient bed and is attached to each of the first guide member and the fixed member, each extending substantially perpendicular to the recumbent direction. Each of the fixing members provided to engage the first guiding member to allow each of the fixing members to be independently guided in the transverse direction along the one side. And a first locking device for locking in at least one transverse position of the corresponding one of the first guide members. This allows for fast patient fixation and even reduction or removal of additional fixation devices. In principle, the first guide member arranged on each side of the patient bed may be integrally formed.

  In another aspect of the present invention, the patient bed is disposed along at least a portion of the patient bed and extends substantially parallel to the patient bed recumbent direction, is disposed on the MRRF antenna device, and is disposed on the second induction member. A second coupling member provided to engage the second guiding member to allow guided movement of the MRRF antenna device along the MRRF antenna device, and at least one of the MRRF antenna device at the second guiding member. A second locking device for locking in one position. Thereby, the MRRF antenna device can be adjusted to any position along the second guiding member, and a close fit and high signal-to-noise ratio of the MRRF antenna device in close proximity to the patient's perineum can be achieved. . The locking device may include a non-positive locking mechanism such as a screw or a locking handle, or any other mechanism deemed appropriate to those skilled in the art.

  In another embodiment, the second guide member of the patient bed has at least one recess and a second locking device is provided to engage the at least one recess when in positive lock. At least one fixing member. This allows the MRRF antenna device to be positioned relative to the subject's perineum, which is fast, reliable and repeatable. In addition, the second guiding member is an additional non-positive locking mechanism for locking one fixing member in a positive locking position with at least one recess to enhance the positioning reliability of the MRRF antenna device. May be provided.

  In yet another embodiment, the patient bed may further comprise at least a second MRRF antenna device having at least one MRRF antenna enclosed within a housing formed integrally with one of the fixation members. This provides an MR signal with a high signal-to-noise ratio for the upper part of the abdominal region, eg, for kidney imaging, with improved repeatability and reproducibility of MRRF antenna positioning relative to the subject, while at the same time patient The bed is easy for the operator to use, and the application of the MRRF antenna is comfortable for the subject, allowing for fast patient fixation with fewer or even additional fixation devices.

  Another object of the present invention is to provide an abdominal support for supporting the subject's abdominal region, particularly during radiotherapy under magnetic resonance induction, and the recumbent direction in which the subject is intended to lie along the recumbent direction. A magnetic resonance (MR) radio frequency (RF) antenna apparatus for use with a patient bed having at least one MRRF antenna enclosed in a housing having two opposite sides, the top surface of the patient bed An MRRF antenna device that can be placed in a central region of a patient bed. This allows MR signals with high signal-to-noise ratios to be obtained, while at the same time satisfying the sterilization requirements in a simple and fast manner, and providing an efficient workflow for achieving high patient throughput of therapeutic procedures. to enable.

  Preferably, also in order to achieve a large signal-to-noise ratio of the MR signal, the MRRF antenna of the MRRF antenna apparatus is located within the portion of the housing that includes the first third of the housing relative to the lying position of the patient bed It is arranged at the position.

  In a preferred embodiment, the at least one MRRF antenna transmits a magnetic resonance imaging signal for transmitting RF power during a first operating period and during a second operating period that is different from the first operating period. Provided to receive. Thereby, a compact design of the MRRF antenna can be achieved, and RF interference due to mutual coupling between separate transmitting and receiving MRRF antennas can be prevented in advance.

  In yet another embodiment, the MRRF antenna device further comprises at least one magnetic resonance (MR) marker encapsulated within the housing. The MR marker can enable simple and accurate positioning of the subject and the platform and verification of the position.

  In yet another embodiment, the MRRF antenna device further comprises at least one optical marker disposed on the outside of the housing. Thereby, the patient table can be placed in a fast and reliable manner, and the mutual alignment of the coordinate system of the MR radiation therapy device can be verified immediately. This can be particularly advantageous for MR-based radiotherapy planning and simulation. Preferably, the at least one optical marker is placed on the top surface of the MRRF antenna apparatus, which is distal to the patient bed in the operating state.

  In at least one tomographic plane parallel to the upper surface of the patient bed, the housing of the MRRF antenna device may have an elliptical cross-sectional area extending in the recumbent direction. Thereby, a natural recumbent position having a high degree of comfort for the subject can be achieved. Preferably, the housing is designed with an aspect ratio of cross-sectional area greater than 2, and most preferably an aspect ratio greater than 3.

  These and other aspects of the invention are apparent from and will be elucidated with reference to the embodiments described hereinafter. However, such embodiments do not necessarily represent the full scope of the invention, and therefore the claims and specification are referred to in order to interpret the scope of the invention.

FIG. 3 shows a schematic top view of a patient bed according to an embodiment of the present invention. FIG. 2 shows a schematic cross-sectional view in the AA ′ direction of a patient bed according to the embodiment of FIG. 1. Figure 2 shows a schematic cross-sectional view in the BB 'direction of a patient bed according to the embodiment of Figure 1;

  FIG. 1 shows a schematic top view of a patient bed according to an embodiment of the present invention. The patient bed is used in a radiotherapy (RT) system having a linear accelerator (LINAC) unit to accelerate elementary particles such as electrons or mesons for radiotherapy purposes. The RT system is guided by a magnetic resonance (MR) imager. Such MR imaging RT systems are well known from the prior art and are therefore not described in further detail herein. The use of a patient bed should not be understood to be limited to MR imaging RT systems, but rather ionizing radiation for therapeutic purposes, such as proton beams, ion beams, focused ultrasound (FUS), or shock wave devices. And applications in MR imaging systems integrated with other treatment devices using at least one of ultrasonic energy.

  The patient bed includes an abdominal support 14 for supporting the abdominal region 18 of the subject 12 during radiation therapy under magnetic resonance induction, and the recumbent direction 10 intended for the subject 12 to lie along the recumbent direction. And have. Further, the patient bed has two leg support portions 16 for supporting the leg 22 of the subject from below, and a bar-like shape, each of which is arranged in parallel with the patient bed recumbent direction 10 along each side of the patient bed. And two fixing members 24 designed in the above.

  The position of the fixing member 24 transverse to the recumbent direction 10 can be adjusted. For this purpose, the patient bed comprises a first guide member 34 designed as a duct, which is arranged on each side of the patient bed. Each of the first guide members 34 extends substantially perpendicular to the recumbent direction 10. A first coupling member 36 designed as a rail is attached to each of the fixation members 24 on a surface adjacent to the patient bed upper surface 26 on which the patient is placed, along a corresponding one of the first guide members 34, Each securing member 24 is provided to engage the first guiding member 34 to allow independently guided movement in the transverse direction. The first coupling member 36 may engage the first guide member 34 by a ball bearing or caster or any other means deemed appropriate to those skilled in the art.

  A first locking device 38 is provided to lock each of the securing members 24 in any transverse position on a corresponding one of the first guide members 34. The first locking device 38 is designed as a mechanical brake having a brake pad that engages with the first guide member 34 and can be released by the operator pressing a button that can be placed on the securing member 24. Good. In principle, any other locking mechanism deemed appropriate by those skilled in the art may be applied.

  A coil-type magnetic resonance (MR) radio frequency (RF) antenna 50 and a housing 52 having two opposite sides 54 extending generally parallel to the recumbent direction 10 in the patient bed central region 30 at the patient bed top surface 26. A magnetic resonance (MR) radio frequency (RF) antenna device 48 is disposed. The central region is located relative to the longitudinal axis of the patient bed, away from the long distal end of the patient table. The MRRF antenna 50 is enclosed within the housing 52 such that the housing 52 completely encompasses the MRRF antenna 50. In a tomographic plane parallel to the upper surface 26 of the patient bed, the housing 52 has an elliptical cross-sectional area that extends along the recumbent direction 10 and exhibits an aspect ratio greater than 4. The MRRF antenna 50 is disposed within the housing 52 within the portion of the housing that includes the first third of the housing 52 relative to the lying direction 10 of the patient bed. The MRRF antenna 50 is provided for transmitting RF power during a first operating period and for receiving a magnetic resonance imaging signal during a second operating period that is different from the first operating period. The Methods of using a transmit / receive switch to supply RF power to the MRRF antenna 50 in a first time period and to supply the MRRF signal received by the MRRF antenna 50 to the signal processing unit are well known in the prior art. And therefore will not be described in further detail herein.

  The patient bed is designed as a rail and includes a second guide member 40 disposed along the patient bed abdominal support 14 and extending generally parallel to the patient bed recumbent direction 10 and parallel to the patient bed lower surface 28. . A second coupling member 42 designed as a caster is disposed on the MRRF antenna device 48 to allow for guided movement of the MRRF antenna device 48 along the second guiding member 40. 32 is provided to engage the second guide member 40. The second guide member 40 has a plurality of recesses spaced equidistantly designed as a through opening in a direction perpendicular to the recumbent direction 10. A second locking device 44 having a locking member designed as a spring-loaded bolt (not shown) provided to engage one of the recesses that builds a positive lock in the locked position is an MRRF antenna device 48. Attached to. The positive lock can be released by pulling the bolt against the spring force of the spring loaded bolt with a handle (not shown) provided outside the housing 52 of the MRRF antenna device 48.

  While lying on the patient bed along the recumbent direction 10, the subject 12 is supported by the abdominal support 14 in the abdominal region 18 and by the two leg supports 16 on both feet 22. In practice, the subject 12 is also supported by the back of the patient bed not shown for purposes of clarity.

  In preparation for the operational state, the position of the MRRF antenna device 48 is in the unlocked positive lock state, and the portion of the MRRF antenna device 48 leading to the recumbent direction 10 is proximal to the perineum 20 of the subject. It is adjusted along the 2nd guide member 40 so that it may exist. In this position, the positive lock is re-established by releasing the handle.

  The subject's legs 22 are then positioned such that each side 54 of the MRRF antenna device 48 is proximal to the inside of each of the subject's legs 22. The first locking device 38 of the securing member 24 is then released by pressing the corresponding button, and the securing member 24 is in an operational state where each of the securing members 24 is proximal to one outside of the subject's leg 22. Until the subject's leg 22 is shifted along the first guide member 40. In this position, the first locking device 38 is re-engaged to lock the securing member 24 in these positions on the first guide member 34. Thus, a well-defined relative position of the subject 12 and the MRRF antenna 50 where the MRRF antenna 50 is placed in close proximity to the subject's perineum 20 can be established quickly and reproducibly. At the same time, the position of the subject is fixed with a high degree of comfort for the subject 12 by the fixing member 24 and further fixing means can be removed.

  Fast and reliable alignment of the patient bed with respect to the coordinate system of the MR imaging system is located on the upper surface outside the housing 52 of the MRRF antenna device 48 and in operation, distal to the patient bed upper surface 26. This can be done by using the marker 56.

  In operation, the MR marker 58 encapsulated within the housing 52 and formed by the amount of magnetic resonance active nuclides provides an MRRF signal upon RF excitation that can be received by the RF antenna of the RT system under MR imaging guidance. This enables simple and accurate positioning of the subject and the patient bed and verification of the position.

  Further, the radiation detection device 60 is enclosed in the housing 52. The radiation detection device 60 is disposed at a position within the portion of the housing 52 that includes the first third of the housing 52 with respect to the recumbent direction 10 of the patient bed, so that in the operating state, the radiation detection device 60 is Although it is close to the radiation exposure area inside the subject 12, it is arranged outside. The output cable 62 of the radiation detection device 60 exits the housing 52 through a cable feed to provide a signal depending on the radiation intensity to the control unit (not shown) of the RT system under MR imaging guidance. . Alternatively, the signal according to the radiation intensity may be transmitted to the control unit in a wireless manner. Those skilled in the art are familiar with devices and methods for this purpose. The control unit determines the stray radiation dose at a known location for quality assurance purposes and for detection of deviations from the predetermined planning data stored in the control unit memory. Provided to integrate the signal over time.

  The patient bed has a second MRRF antenna device 48 ′, 48 ″ having the same MRRF antenna 50 ′, 50 ″ as in the first MRRF antenna device 48. The second MRRF antenna devices 48 ′ and 48 ″ are enclosed in housings 52 ′ and 52 ″ formed integrally with one of the fixing members 24 ′ and 24 ″, as indicated by broken lines in FIG. Is done. The second MRRF antenna device 48 ′, 48 ″ has improved repeatability and reproducibility of positioning of the MRRF antenna relative to the subject, for simple subject fixation and MR imaging of the subject's kidney. Allows a high signal-to-noise ratio.

  While the invention has been illustrated and described in detail in the drawings and foregoing description, such illustration and description are to be considered exemplary or exemplary and should not be considered as limiting; It is not limited to the disclosed embodiments. Other variations of the disclosed embodiments can be understood and attained by those skilled in the art from a study of the drawings, the specification, and the appended claims, in carrying out the claimed invention. In the claims, the word “comprising” does not exclude other elements or steps, and the indefinite article “a” or “an” does not exclude a plurality. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measured cannot be used to advantage. Any reference signs in the claims should not be construed as limiting the scope.

DESCRIPTION OF SYMBOLS 10 Recumbent direction 12 Subject 14 Abdominal support part 16 Leg support part 18 Abdominal area 20 Perineum 22 Leg 24 Fixing member 26 Patient bed upper surface 28 Patient bed lower surface 30 Patient bed center area 32 Patient bed opening 34 1st guide member 36 1st Connecting member 38 First locking device 40 Second guiding member 42 Second connecting member 44 Second locking device 46 Recess 48 MRRF antenna device 50 MRRF antenna 52 Housing 54 Side surface 56 Optical marker 58 MR marker 60 Radiation detection device 62 Output cable

Claims (12)

  For use with a patient bed having an abdominal support for supporting the subject's abdominal region, and the recumbent direction intended for the subject to lie down, particularly during radiation therapy under magnetic resonance induction A magnetic resonance (MR) radio frequency (RF) antenna device,
  In an MRRF antenna device having at least one MRRF antenna encapsulated in a housing having two opposite sides and being arranged in a patient bed central region on the upper surface of the patient bed,
  An MRRF antenna device, further comprising a radiation detection device enclosed in the housing. A patient bed having an abdominal support for supporting a subject's abdominal region during magnetic resonance guided therapy;
Wherein is placed on the patient bed center region in the upper surface of the patient bed, and MRRF antenna device according to claim 1,
Two leg supports for supporting the subject's leg from below, and in at least one operating state, each side of the MRRF antenna device is proximal to the inside of each of the subject's legs. Provided to be
In the at least one operating state, the MRRF antenna device is provided to be proximal to the subject's perineum. A fixing member having the recumbent direction intended for the subject to lie along the recumbent direction and arranged parallel to the recumbent direction of the patient bed along each of the patient bed sides, The patient bed of claim 2 , wherein in at least one operating state, each of the fixation members is provided to be proximal at least outside one of the subject's legs. A first guide member disposed on each side of the patient bed, each extending substantially perpendicular to the recumbent direction, and attached to each of the fixed members, along a corresponding one of the first guide members A first connecting member provided to engage with the first guiding member to allow each of the fixing members to be independently guided in a transverse direction; and The patient bed of claim 3 , further comprising a first locking device for locking in at least one transverse position of the corresponding one of the first guide members. A second induction member disposed along at least a portion of the patient bed and extending substantially parallel to the recumbent direction of the patient bed; and the MRRF antenna disposed in the MRRF antenna device and along the second induction member A second coupling member provided to engage with the second guiding member to enable guided movement of the device, and the MRRF antenna device at least one position on the second guiding member; The patient bed according to claim 3 or 4 , further comprising: a second locking device for locking with. The second guide member has at least one recess, and the second locking device comprises at least one securing member provided to engage the at least one recess when positively locked; The patient bed according to claim 5 . 7. The apparatus of claim 2 , further comprising at least a second magnetic resonance (MR) radio frequency (RF) antenna device having at least one MRRF antenna enclosed in a housing formed integrally with one of the fixing members. The patient bed according to any one of the above. At least one MRRF antenna for transmitting RF power during a first period of operation and for receiving a magnetic resonance imaging signal during a second period of operation different from the first period of operation. are provided, MRRF antenna device according to claim 1. 9. The MRRF antenna apparatus according to claim 1 or 8, further comprising at least one magnetic resonance (MR) marker enclosed within the housing. 10. The MRRF antenna apparatus according to claim 1, 8 or 9 , further comprising at least one optical marker disposed outside the housing. The MRRF antenna device according to claim 1, 8, 9, or 10, wherein the housing has an elliptical cross-sectional area extending in the recumbent direction in at least one tomographic plane parallel to the upper surface of the patient bed. . Ionizing radiation and ultrasound energy for therapeutic purposes induced by a magnetic resonance (MR) imaging device having a patient bed having at least one MRRF antenna device according to claim 1, 8, 9, 10 or 11. A treatment system using at least one of the above.

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